--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/lib/mmap-util.c	Fri Aug 09 12:15:38 2002 +0300
@@ -0,0 +1,88 @@
+/*
+ mmap-util.c - Memory mapping utilities
+
+    Copyright (c) 2002 Timo Sirainen
+
+    Permission is hereby granted, free of charge, to any person obtaining
+    a copy of this software and associated documentation files (the
+    "Software"), to deal in the Software without restriction, including
+    without limitation the rights to use, copy, modify, merge, publish,
+    distribute, sublicense, and/or sell copies of the Software, and to
+    permit persons to whom the Software is furnished to do so, subject to
+    the following conditions:
+
+    The above copyright notice and this permission notice shall be
+    included in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+#include "lib.h"
+#include "mmap-util.h"
+
+static void *mmap_file(int fd, size_t *length, int access)
+{
+	*length = lseek(fd, 0, SEEK_END);
+	if ((off_t)*length == (off_t)-1)
+		return MAP_FAILED;
+
+	if (*length == 0)
+		return NULL;
+
+	i_assert(*length > 0 && *length < INT_MAX);
+
+	return mmap(NULL, *length, access, MAP_SHARED, fd, 0);
+}
+
+void *mmap_ro_file(int fd, size_t *length)
+{
+	return mmap_file(fd, length, PROT_READ);
+}
+
+void *mmap_rw_file(int fd, size_t *length)
+{
+	return mmap_file(fd, length, PROT_READ | PROT_WRITE);
+}
+
+void *mmap_aligned(int fd, int access, off_t offset, size_t length,
+		   void **data_start, size_t *mmap_length)
+{
+	void *mmap_base;
+
+#ifdef HAVE_GETPAGESIZE
+	static int pagemask = 0;
+
+	if (pagemask == 0) {
+		pagemask = getpagesize();
+		i_assert(pagemask > 0);
+		pagemask--;
+	}
+
+	*mmap_length = length + (offset & pagemask);
+
+	mmap_base = mmap(NULL, *mmap_length, access, MAP_SHARED,
+			 fd, offset & ~pagemask);
+	*data_start = mmap_base == MAP_FAILED || mmap_base == NULL ? NULL :
+		(char *) mmap_base + (offset & pagemask);
+#else
+	*mmap_length = length + offset;
+
+	mmap_base = mmap(NULL, *mmap_length, access, MAP_SHARED, fd, 0);
+	*data_start = mmap_base == MAP_FAILED || mmap_base == NULL ? NULL :
+		(char *) mmap_base + offset;
+#endif
+
+	return mmap_base;
+}
+
+#ifndef HAVE_MADVISE
+int madvise(void *start, size_t length, int advice)
+{
+}
+#endif